The present invention relates to rotational coupling means disposed on an adapter or holder for load elements or cutter heads and the like coupled to a hub of a holder mounted for rotation in any of several tools such as a table drill press, radial drill presses, vertical mill, horizontal mill, lathe tail stock, reamers and the like. More particularly, the invention relates to a multi-machine cutter holder and in which there is provided in the load element or cutter structure a key slot extending diametrically along a mating surface of the load element or cutter head having its face mating with or mounted upon the hub of the flanged element and in which abutmentmember or members are balanced about an axis of the flanged piece for preventing the load element from separately rotating independently of the holder.